Location: Kimper, Kentucky, USA • Sector: Food & Beverage

The Client:
The Kellogg Company is the world’s leading cereal company; second largest producer of cookies, crackers, and savory snacks; and a leading North American frozen foods company.

The Client's Needs:
ADI Systems first started providing wastewater treatment solutions to the Kellogg Company Pikeville Plant (formerly Mountaintop Baking) in Kimper, Kentucky, USA, in the late 1990s.

In 1999–2000, ADI Systems was awarded a design/build contract to upgrade the wastewater treatment system due to production expansion at the plant. The upgrade included an
ADI-Hybrid anaerobic reactor followed by a sequencing batch reactor (ADI-SBR).

Recently, due to further increases in production, the wastewater treatment system required additional upgrades to handle the increased flow and organic loads. The plant was also required to produce a higher quality effluent.

The Solution:
Kellogg Company Pikeville Plant upgraded its existing anaerobic and aerobic wastewater treatment facility to an anaerobic membrane bioreactor (ADI-AnMBR) and a membrane bioreactor (ADI-MBR).

The upgraded system includes anaerobic pretreatment complete with a continuous stirred-tank reactor and an AnMBR tank. This is followed by an aerobic polishing system which includes a pre-aeration tank and an MBR tank. The AnMBR and MBR tanks are housed in a single, partitioned modular tank.

The Results:
ADI Systems designed the AnMBR and MBR system and effectively managed the project to allow for quick installation and reuse of some of the existing equipment on-site. Installing the new treatment system did not require any curtailment of plant production.

The AnMBR process provides very effective anaerobic digestion of the plant’s wastewater, with an average effluent COD concentration of 160 mg/l and a negligible TSS concentration. Biogas, a by-product of anaerobic digestion, is currently burned in a flare with future plans to use a portion of it in the wastewater treatment plant’s boiler to offset natural gas costs. The aerobic MBR system polishes the AnMBR effluent, then a series of chlorination and dechlorination tanks provide disinfection for the MBR effluent.

The upgraded system has demonstrated an overall COD removal of greater than 99.5 percent and an average effluent COD concentration of 62 mg/l, BOD of 9 mg/l, and negligible TSS (<1 mg/l). Other parameters such as NH³-N, FOG, DO, E. coli, etc., all meet strict discharge limits, allowing for the final effluent to be discharged directly to a local creek. McCoy & McCoy Laboratories monitors the final effluent quality and reports the results on a monthly basis.

The system has provided the company with savings on operating and maintenance costs and allowed for a 25 percent increase in design flow and 44 percent increase in design organic load.

In the future, the Kellogg Company Pikeville Plant will also be able to treat waste jams, which are currently handled offsite. This will result in even more cost savings, thereby further justifying installation of the new wastewater treatment system.